A rubber tire which is to be mounted to a vehicle or the like is cured, so that the tire is hardened into a final shape and is provided with sufficient strength and resiliency, but since a tire after it is cured is hot and soft and thus, the tire is transferred into a postcure inflator and is cooled and hardened therein.
As shown in FIG. 5, this post-curing inflator comprises a pair of flanges for closing openings in left and right side surfaces of the tire, and a hoisting and lowering device for sliding the upper flange, and a tire after it is cured is sandwiched between the flanges and tightly closed and then, compressed gas is allowed to blow into the tire and the tire is cooled for a predetermined time in a state in which the tire is expanded.
If the compressed gas is allowed to blow into the tire, a tire expansion load is applied between the flanges. Therefore, there is provided a locking and unlocking mechanism which connects center portions of the flanges such that the flanges can withstand the load, and releases the connection therebetween when the tire is inserted between the flanges or removed therefrom.
This locking and unlocking mechanism mainly comprises a lower flange 57 onto which a tire is horizontally placed, an upper flange 58 fitted to the lower flange 57, and a male rod 59 and a male mold 60 which can slide with each other in a direction in which the upper and lower flanges approach each other but maintain a constant distance between the male rod 59 and the male mold 60 in a direction in which the flanges are separated from each other.
The male rod 59 projects from the upper flange downward, and a tip end of the male rod 59 and a tip end of the male mold 60 are engaged with each other.
If a tire after it is cured is placed on the lower flange 57, the upper flange 58 is lowered onto the tire, and the openings of the left and right sides are closed.
After the tire is closed, compressed gas is allowed to blow into the tire, an expansion load is supported by the male rod 59 and the male mold 60, and the tire is cooled and hardened.
The openings of the tire are closed for expanding the tire between the upper and lower flanges. That is, in order to bring the flanges 57 and 58 into tight contact with each other, since the openings of the tire are converged inwardly and the tire after it is cured is hot and soft, it is necessary to bring the flanges 57 and 58 close to each other more than a predetermined width which cools and hardens the flanges, and to bring a rim into abutment against a bead portion.
Therefore, in the case of a conventional locking and unlocking mechanism, it is necessary to deeply insert the male rod 59 into the male mold 60 to bring the flanges 57 and 58 close to each other.
Therefore, a deep male mold 60 is required and there is a problem that the entire device becomes long and large in size.
Further, in the conventional locking and unlocking mechanism, since there is a locking and unlocking driving section on the side of the upper flange, there is a problem that the hoisting and lowering device of the upper flange also becomes large in size.
The present invention has been accomplished to solve the conventional problems, and it is an object of the invention to provide a locking and unlocking mechanism of a post-curing inflator in which a male rod is disposed on the side of a lower flange and a male mold is disposed on the side of an upper flange, a slide portion is formed on the male rod, and a locking and unlocking mechanism driving section is disposed so that the male mold is simplified in structure and reduced in weight, and the entire device including the upper flange hoisting and lowering device is reduced in size and weight.